U.S. patent number 5,411,443 [Application Number 08/257,660] was granted by the patent office on 1995-05-02 for dragchain substitute.
Invention is credited to Karl Meier, Josef Steff, Karl-Heinz Trieb.
United States Patent |
5,411,443 |
Meier , et al. |
May 2, 1995 |
Dragchain substitute
Abstract
A dragchain substitute in the form of a line guiding assembly
comprising at least one line receiving channel for receiving at
least one line loosely disposed therein. At least one of the
channel walls of each line receiving channel is designed in
projecting manner and resilient towards the channel interior
relative to a channel wall supporting it, such that the line can be
urged from outside of the line receiving channel through the
resilient channel wall and into the interior of the line receiving
channel and is enclosed in the line receiving channel after said
resilient channel wall has resiled.
Inventors: |
Meier; Karl (8548 Heideck,
DE), Steff; Josef (8831 Meinheim, DE),
Trieb; Karl-Heinz (8820 Gunzenhausen, DE) |
Family
ID: |
8207379 |
Appl.
No.: |
08/257,660 |
Filed: |
June 9, 1994 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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805685 |
Dec 10, 1991 |
5322480 |
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Foreign Application Priority Data
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Nov 26, 1991 [EP] |
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91120167 |
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Current U.S.
Class: |
474/145; 191/12C;
474/147; 474/273 |
Current CPC
Class: |
F16G
13/16 (20130101); F16L 3/015 (20130101); H02G
11/006 (20130101) |
Current International
Class: |
F16L
3/015 (20060101); F16G 13/16 (20060101); F16L
3/01 (20060101); F16G 13/00 (20060101); F16H
057/02 () |
Field of
Search: |
;474/100,144-149,273
;191/12C,12R,12.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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712656 |
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Jun 1965 |
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CA |
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18193 |
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Oct 1980 |
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EP |
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490022 |
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Jun 1992 |
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EP |
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436373 |
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Nov 1925 |
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FR |
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3300495 |
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Jul 1983 |
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FR |
|
1288769 |
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Feb 1987 |
|
SU |
|
1534596 |
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Jan 1990 |
|
SU |
|
Primary Examiner: Schoeppel; Roger J.
Attorney, Agent or Firm: Weker; Dena Meyer
Parent Case Text
This application is a division of application Ser. No. 07/805,685,
filed Dec. 10, 1991, now U.S. Pat. No. 5,322,480.
Claims
We claim:
1. A line receiving channel for a dragchain substitute comprising a
continuous, uninterrupted floor portion, a cover portion and
sidewall portions capable of containing at least one single-core or
multi-core line loosely disposed therein, the line receiving
channel being composed of material with good slidability so that an
upper length of the channel is slidable on a lower length of the
channel, said channel also provided with a multiplicity of
transverse separations spaced from each other in the longitudinal
direction of the channel and extending through the cover portion
and continuing in the sidewall portions at least to a location near
the floor permitting the line channel to be able to form a loop
characterized in that, of the cover portion and the sidewall
portions at least one of these portions is designed in a projecting
manner and is resilient towards the channel interior relative to a
channel wall portion supporting said portion, such that a line can
be urged from outside of the line receiving channel into the
interior of the channel through said resilient portion and is
enclosed therein.
2. A line receiving channel according to claim 1, that is
substantially of rectangular cross-section and wherein the cover
has a longitudinal separation in such a manner that it has at least
one spring portion projecting from one of the side walls.
3. A line receiving channel according to claim 2, wherein the
longitudinal separation extends approximately in the middle of the
cover such that two resilient cover portions are formed, each
projecting from one of the two sidewalls and extending towards each
other.
4. A line receiving channel according to claim 2, wherein the cover
and the first side wall are subdivided by the transverse
separations into individual resilient lugs.
5. A line receiving channel according to claim 1, wherein the first
side wall is resilient towards the channel interior.
6. A line receiving channel according to claim 1 wherein the cover
portion, floor portion and side wall portion are comprised of a
metal with good slidability.
7. A line receiving channel according to claim 1, wherein the
transverse separations comprise transverse grooves having widened
groove bottoms.
8. A line receiving channel according to claim 7, wherein each
groove bottom widens into a T-shape.
9. A line receiving channel according to claim 1 wherein the cover
portion, floor portion, and side wall portions are comprised of an
elastic plastic material with good slidability.
10. A line receiving channel according to claim 9 wherein the
elastic plastic material is polypropylene.
11. A line receiving channel according to claim 1 wherein a
hold-down means is disposed therein which is capable of holding
down a line core between a stationary line assembly end and an end
portion of a movable line assembly end and keeps the core to the
channel floor.
12. A line receiving channel according to claim 11, wherein the
hold-down means is constituted by two hold-down rails which extend
longitudinally between the two opposing side walls and which extend
at a clear distance from the channel floor.
13. A line receiving channel according to claim 1 further
comprising a line separating wall projecting from the floor portion
in a direction towards the cover portion.
14. A line receiving channel according to claim 13 wherein the line
separating wall is parallel to the side walls portions.
15. A line receiving channel according to claim 13 wherein the line
separating wall is located in the middle of the floor portion.
Description
FIELD OF THE INVENTION
A dragchain substitute in the form of a line guiding assembly
comprising at least one line receiving channel for receiving at
least one line loosely disposed therein is provided.
BACKGROUND OF THE INVENTION
Many problems exist with conventional dragchain assemblies having
one or more chain belts of metal or plastics material in which
individual lines are guided. Many of these problems are described
in European Patent Application 91105430.2. When the stationary
means and the reciprocable means are arranged in a superimposed
manner and when the dragchain exceeds a certain length with respect
to the necessary path of movement of the movable means, the upper
length of the dragchain is deposited on the lower length thereof.
This results in a high mechanical load on the dragchain, which can
be prevented by way of an intermediate ceiling in the form of a
slide plate in a guiding channel for the dragchain, with the upper
length of the dragchain being deposited on the slide plate. An
additional problem is that the dragchain may cause considerable
movement noise.
The solution described in EP91105430.2 for overcoming this problem
consists in providing the line or line assembly to be guided, on
the side where upper length and lower length are facing each other,
with a sliding means of good slidability which is effective in the
longitudinal direction of the line and prevents friction between
upper length and lower length also in case of long line lengths.
One of the solution possibilities described in EP91105430.2
consists in a line receiving channel in which one or more lines to
be guided are loosely disposed and which consists of a material
having good slidability. Various possibilities for such a line
receiving channel are shown in the figures of EP91105430.2.
FIG. 16 shows a solution described in EP91105430.2 which consists
of a line receiving channel for a ribbon cable having associated
therewith a sliding means in the form of a sliding band disposed on
one side of the ribbon cable and projecting on both sides beyond
the longitudinal edges of the cable jacket. From each of the two
portions projecting beyond the ribbon cable, a multiplicity of
holding pins spaced apart in the longitudinal direction of the
ribbon cable upstands beyond the cable thickness, with the free
ends of the holding pins being bent onto the face of the cable
jacket remote from the sliding band. With this type of line
receiving channel it is either necessary to introduce the ribbon
cable from one end of the line receiving channel underneath the
bent holding pins. Alternatively, the holding pins can be mounted
only after placement of the ribbon cable on the sliding band. A
third possibility consists of mounting to the sliding band holding
pins which are first upstanding in straight manner and to bend
these holding pins in angular manner across the ribbon cable only
after placement of the ribbon cable on the sliding band.
FIG. 17 also described in EP91105430.2 shows a line receiving
channel that is closed all around, along with the transverse slots
thereof allowing loop formation, with the line or lines to be
guided having to be introduced into the channel from one channel
end.
FIG. 18 also described in EP91105430.2 shows a line receiving
channel that is first open on an upper side so that the line or
lines can be inserted conveniently in the line receiving channel.
Thereafter, the line receiving channel is closed by means of a
multiplicity of spaced apart closure clasps which each bridge the
open channel and are attached thereto for instance by glueing or
welding.
The solutions mentioned either necessitate a specific assembly
expenditure for closing an initially open line receiving channel
after loose insertion of one or more lines, or they require line
introduction from an end of the line channel, which may be
troublesome especially in case of line guiding assemblies of
considerable length and/or lines of low stiffness of their own.
There is a need to provide a line guiding assembly of the type
serving as a dragchain substitute and having at least one line
receiving channel, in which the introduction of the one or more
lines in the line receiving channel is facilitated.
SUMMARY OF THE INVENTION
The invention relates to a dragchain substitute in the form of a
line guiding assembly comprising at least one line receiving
channel having a floor portion, a cover or top portion and sidewall
portions, and at least one single-core or multi-core line loosely
disposed therein. The line receiving channel comprises a first
length and a second length guided parallel thereto, the length ends
being connected to a stationary means and to a means adapted to
reciprocate in the longitudinal direction of the line receiving
channel, respectively, and the two lengths merging with each other
in loop-shaped manner therebetween. The floor portion of at least
one line receiving channel, with which the first and second length
are facing each other, is made of a material with good slidability
for sliding on each other. At least one line of the receiving
channel is provided with a multiplicity of transverse separations
spaced from each other in the longitudinal direction of the channel
and extend through the cover portion and continue in the sidewall
portions at least to a location near the floor portion. These
transverse separations permit at least one line receiving channel
the loop formation between first and second length.
With this line guiding assembly, that includes a cover portion and
sidewall portions of the line receiving channel, at least one of
these portions is designed in a projecting manner and is resilient
towards the channel interior relative to a channel wall portion
supporting the portion, such that the line can be urged from
outside of the line receiving channel into the interior of the line
receiving channel through the resilient portion and is enclosed in
the line receiving channel.
The term projecting as used herein is understood to be the result
when the cover or side portion is fixed only at one end and freely
projects.
The invention provides modifications to the line receiving channel
shown in FIG. 16. The present invention provides that all of the
holding pins or at least the holding pin portions extending beyond
the upper longitudinal side of the ribbon cable are resilient. The
height of the holding pins and the length of their ends projecting
beyond the ribbon cable are chosen such that the ribbon cable can
be urged past the resilient holding pins onto the sliding band and
that the holding pins can return to their normal positions after
this urging operation.
When starting from the line receiving channel as shown in FIG. 17
the present invention provides that a wall of the rectangular line
receiving channel, for instance the cover wall or a sidewall, is
given a longitudinal separation in such a manner that the cover or
sidewall has at least one resilient or spring portion projecting
from another channel wall. The longitudinal separation may extend
in the middle of the cover or sidewall, respectively, or at the
transition thereof to one of the two adjacent channel walls. In the
first-mentioned case, the cover or sidewall has two facing spring
portions projecting towards each other and each extending across
part of the channel width only. In the latter case, the cover or
sidewall has a projecting spring portion extending across the
entire channel width. In the latter case both channel walls
adjoining the longitudinal separation can be made resilient so that
the line or lines can be urged into the line receiving channel
selectively either from the one or the other channel wall of the
two channel walls adjacent the longitudinal separation, or also
with resilient deflection of these two channel walls adjacent the
longitudinal separation.
For facilitating the line or lines into the line receiving channel,
the channel wall formed with the longitudinal separation can be
inclined with its projecting end or ends towards the interior of
the line receiving channel so as to form an aid for line
insertion.
When the line guiding assembly is intended to guide a plurality of
lines or cables, it is either possible to use one single line
receiving channel adapted to receive all lines or cables, or it is
possible to form the line guiding assembly with a plurality of
parallel juxtaposed line receiving channels which are either formed
beside each other in an integrally formed or extruded line
receiving channel assembly or which are combined to form a line
receiving channel unit by fixedly or removably connecting several
individual line receiving channels. Each of these line receiving
channels then has a channel wall with a projecting resilient or
spring portion.
In this line guiding assembly, the longitudinal separation is
preferably formed in the cover portion of the line receiving
channel, such that the channel wall is located on the outside in
the loop-shaped transition portion between the upper length and the
lower length. Transverse separations for enabling the line
receiving channel to bend in loop-shaped manner are arranged in the
cover portion and extend into the adjacent sidewalls up to the
channel floor opposite the cover portion.
The transverse separations are preferably formed by transverse
grooves having groove bottoms widening with respect to the
remaining groove width, for instance in the form of an inverse
T.
In case of relatively long movement distances of horizontally
reciprocable movable means, correspondingly long upper length
dimensions result when the movable means is in that end position
which leads to the shortest lower length dimension. In case of a
rapid movement of the movable means in the direction towards the
loop portion formed between upper length and lower length, in
particular along with a high acceleration of the movable means, the
thrust force acting on the upper length can easily lead to
distortions of the upper length, causing the formation of bulges or
even breaks. This leads to a strong mechanical load of the
dragchain substitute and of the line assembly guided thereby.
The present invention eliminates this problem in that a hold-down
means is disposed in a line guiding channel which holds down the
upper length in the region between the stationary line assembly end
and that end position of the movable line assembly end in which the
lower length is shortest, and keeps the upper length to the floor
of the line guiding channel.
The hold-down means is preferably constituted by two hold-down
rails which extend in the longitudinal direction of the line
guiding channel approximately across the portion between the
stationary line assembly end and that end position of the movable
line assembly end in which the lower length is shortest, and which
each project towards each other from one of the two opposing
sidewall interiors of the line guiding channel and extend at a
clear distance from the floor of the line guiding channel which is
somewhat larger than the thickness of the line assembly.
The features of the hold-down means have significance of their own
and yield advantages irrespective of whether or not the dragchain
substitute has a line receiving channel.
It is particularly advantageous to use the hold-down means with a
dragchain substitute having disposed in its loop-portion a roller
which is movable together with the loop portion and on which the
dragchain substitute performs a rolling motion upon movement of the
line assembly. The roller preferably has a diameter that is greater
than the loop diameter of the line assembly without such roller. In
particularly preferred manner, the roller is loosely disposed in
the loop portion. The roller circumference should have such
friction with respect to the line assembly or the line receiving
channel, respectively, that the line assembly or the line receiving
channel is not lifted off from the roller circumference in case of
a thrust force acting on the upper length. The roller circumference
therefore is composed with a material such as rubber or relatively
soft plastic material which, in cooperation with the material of
the line assembly or the line receiving channel, results in such
frictional force that such lifting-off of the line assembly or of
the line receiving channel from the roller circumference is
avoided.
The roller prevents lasting bulge-like deformations of the line
assembly or of the line receiving channel, respectively, due to a
prolonged standstill of the movable means. The roller can also be
used for predetermining the desired loop diameter. Furthermore, the
roller has the effect of a dampening member which dampens
oscillations occurring in the upper length portion during rapid
reciprocating movements of the movable means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a line guiding assembly according
to the invention, illustrating one single line receiving channel in
perspective manner.
FIG. 2 is a face end view of the line guiding assembly shown in
FIG. 1
FIG. 3 is an end view of a line guiding assembly that is modified
with respect to FIG. 1.
FIG. 4 is an end view of the embodiment shown in FIGS. 1 and 2,
however having a partition inside the line receiving channel.
FIG. 5 is an end view of an embodiment according to FIG. 3,
however, having a partition in the line receiving channel.
FIG. 6 is an end view of a line guiding assembly comprising four
line receiving channels.
FIG. 7 is an end view of a line guiding assembly having three line
receiving channels, each provided with a partition.
FIG. 8 is a view of an embodiment of a line receiving channel
having a longitudinal separation provided between a lateral end of
the cover portion and the adjacent sidewall.
FIG. 9 is a view of an embodiment having a longitudinal separation
provided at the upper end of a sidewall.
FIG. 10 is a view of an embodiment as shown in FIGS. 1 and 2,
however with modified transverse separations.
FIGS. 11 and 12 are schematic side views of a dragchain substitute
having a hold-down means, with FIGS. 11 and 12 showing opposite end
positions of the movable means.
FIG. 13 is a cross-sectional view of a dragchain substitute having
a hold-down means according to FIGS. 11 and 12.
FIGS. 14 and 15 are schematic side views of a dragchain substitute
having a roller disposed in the loop portion.
FIG. 16 is a view of a line receiving channel for a ribbon cable
with sliding means in the form of a sliding band.
FIG. 17 is a view of a line receiving channel that is closed all
around along with transverse slots.
FIG. 18 is a view of a line receiving channel that is first open on
an upperside and closed by plurality of clasp means.
DETAILED DESCRIPTION OF THE INVENTION
The invention is best understood with reference to the accompanying
figures.
FIG. 1 shows in a perspective view a first embodiment of a line
guiding assembly in the form of a line receiving channel 11 which
may be adapted to receive, for example, two juxtaposed round lines
13 and 15 indicated in FIG. 1 by dot and dash lines. The line
receiving channel 11 comprises a floor 17, a left-hand sidewall 19,
a right-hand sidewall 21 and a cover or top 23. Cover 23 is split
by a longitudinal separation 25 extending in the center thereof in
longitudinal direction of the channel, such that a left-hand cover
portion 27 and a right-hand cover portion 29 are formed. Each of
the two cover portions 27 and 29 is slightly inclined towards the
channel interior from its longitudinal lateral edge towards
longitudinal separation 25. This results in a kind of insertion aid
facilitating urging of a line into the interior of the line
receiving channel 11.
The line receiving channel 11 is provided with transverse
separations 31 which are arranged in periodically successive manner
in the longitudinal direction thereof and which extend through both
cover portions 27 and 29 and into the respective adjacent sidewall
19 and 21, respectively, preferably up to the transition of the
respective sidewall 19 and 21, respectively, to the floor 17.
The line receiving channel 11 consists of an elastic, resilient
material. Due to this resilience, the cover portions 27 and 29 can
be resiliently deflected towards the channel interior when a line
or a cable is to be urged into line receiving channel 11. This
resilience is enhanced by the presence of the transverse
separations 31.
When the line guiding assembly, between a stationary means and a
means adapted to reciprocate relative to the latter, is of such a
length that the particular upper length is deposited on the lower
length, the line receiving channel 11 is made of a material having
good sliding properties, so that upper length and lower length have
good slidability for sliding on each other with their floor
portions. The loop formation at the transition between upper length
and lower length is rendered possible by the transverse separations
31.
However, it is also possible to produce only the floor 17 of
material with good slidability, or to apply a material with good
slidability to the floor 17.
The line receiving channel preferably is made of an elastic plastic
material with good slidability, such as polypropylene. Other
plastic materials or metals, for instance steel, may be used as
well.
The height of the sidewalls 19 and 21, the inclination of the two
cover portions 27 and 29 as well as the width of the longitudinal
separation 25 are selected such that the free ends of the cover
portions 27 and 29 can resume their original positions when the
cables or lines 13 and 15 have been urged through the
longitudinally split cover 23 onto the floor 17 of the line
receiving channel 11. In FIG. 1, the thickness of the lines are
thinner or flatter than the dimensions of the line receiving
channel shown.
FIG. 2 shows in an end view the embodiment of a line receiving
channel 11 depicted in FIG. 1 together with the round lines 13 and
15 accommodated therein.
A similar view is shown in FIG. 3, however, relating to an
embodiment of a line receiving channel 11 in which the separated
cover portions 27 and 29 are not inclined, but extend parallel to
the floor 17.
The embodiments shown in FIGS. 1 to 3 have two round lines 13 and
15 that are arranged beside each other without separation.
Alternatively, FIGS. 4 and 5 show the round lines separated by a
line separating wall 33 in the middle of the line receiving channel
11.
The transverse separations 31 extend also through the line
separating walls 33 in order to enable loop formation of the
respective line receiving channel 11 without any problem.
FIGS. 6 and 7 illustrate end views of embodiments in which the line
guiding assembly according to the invention each comprises a
plurality of parallel juxtaposed line receiving channels.
FIG. 6 shows an integrally formed line guiding assembly 35 that has
four parallel line receiving channels 11 disposed therein. each
having a round line 13 arranged therein. The longitudinal
separation 25 of each one of these line receiving channels 11
extends at the transition between the associated cover 23 and the
right-hand sidewall of each line receiving channel 11. The cover 23
of each line receiving channel 11 is obliquely inclined downwardly
so as to facilitate urging of a line into the respective line
receiving channel 11. The transverse separations 31 extend through
all channel sidewalls in order to enable loop formation.
FIG. 7 shows a line guiding assembly 35 having three parallel line
receiving channels 11 each suited to receive two round lines 13 and
15 and provided with central line separating walls 33. The covers
23 of the individual line receiving channels 11 are each provided
in their center with a longitudinal separation 25, and the thus
created left-hand and right-hand cover portions 27, 29 are each
inclined obliquely downwardly towards the associated line
separating wall 33.
In this embodiment the transverse separations 31 extend through all
channel sidewalls and through all line separating walls 33 so as to
enable bending in the region of the loop transition between upper
length and lower length without any problem.
In the illustrated examples, round lines 13, 15 are inserted in the
line receiving channels 11. Of course, it is also possible to
insert ribbon cables, for instance in the line receiving channels
11 shown in FIGS. 2 and 3.
FIG. 8 illustrates an end view of a line receiving channel 11 in
which the entire cover portion 23 is designed in projecting manner.
In this embodiment, a longitudinal separation 25 is formed between
the free end of the cover portion 23 and the adjacent sidewall
21.
FIG. 9 shows an end view of an embodiment in which a sidewall 19 is
designed in projecting manner, with a longitudinal separation 25
being formed between the upper end of this sidewall 19 and the
cover portion 23. In this embodiment the sidewall 19 is resilient
towards the channel interior. A round line 13 can thus be urged
into the channel interior by resiliently urging sidewall 19
inwardly.
FIG. 10 shows a modification of the embodiment illustrated in FIG.
1. The difference between FIG. 1 and FIG. 10 is that the transverse
separations 31 are constituted by transverse grooves whose groove
bottoms 32 are widened in the form of an inverted T. This widening
of the groove bottom improves the flexural mobility of the line
receiving channel 11 and eliminates the risk that uncontrolled
tearing occurs at the lower groove ends.
FIGS. 11 to 13 depict in schematic manner an embodiment of a
dragchain substitute having hold-down rails. The cross-sectional
view of FIG. 13 shows an upwardly open line guiding channel 39
having sidewalls 41 and 43. On a channel floor 45, there is located
a line assembly 47 including two juxtaposed ribbon cables each
disposed between two laterally opposite sliding channels 51, the
four sliding channels along with the ribbon cables 49 being
combined to form the line assembly 47 by means of transverse lugs
53 spaced apart in the longitudinal direction of the line assembly
47. At a slight distance above the transverse lugs 53, there are
located the two hold-down rails 37 projecting each from the inside
of one of the two sidewalls 41 and 43 into the interior of the line
guiding channel 39.
As outlined in FIGS. 11 and 12, the end of the lower length 57
remote from the loop portion 55 is connected to the upper end of a
stationary foot plate 59. The free end of the upper length 61
remote from the loop portion 55 is connected to an upstanding
movable head plate 63 serving as a spacer member. The foot plate 59
is connected to a stationary means. The head plate 63 is connected
to a reciprocable means.
Upon movement of the movable means between its two end positions,
the head plate 63 moves between two end portions which are shown in
FIGS. 11 and 12. The hold-down rails 37 are disposed between the
position of the stationary foot plate 59 and the left-hand end
position of the head plate 63 as shown in FIG. 12, with the lower
length 57 being shortest in this position. The hold-down rails 37
are restricted to this portion of the path of movement of the
movable head plate 63, in order not to collide on the one hand with
the loop portion 55 of the line assembly 47 and since on the other
hand distortions and bulges due to rapid movement of the head plate
63 without the provision of the hold-down rails 37 occur only when
a particularly long upper length 61 is pushed by the head plate
63.
For rendering possible that the head plate 63 projecting from above
into the line guiding channel 39 can be moved in the line guiding
channel 39 without being hindered by the hold-down rails 37, the
head plate 63 in the embodiment shown in FIG. 13 is provided on
both sides with one recess 65 each, into which one of the two
hold-down rails 37 can project such that movement can take place in
unhindered manner.
It would also be possible to reduce the width of the head plate to
such an extent that it is smaller than the clear distance between
the two facing hold-down rails 37.
FIGS. 14 and 15 illustrate a schematic side view of a dragchain
substitute having a roller 67 loosely disposed in its loop portion.
The loop portion 55 of the line assembly 47 performs a rolling
motion on the circumference of the roller 67 when a movable means
69 is moved with respect to a stationary means 71 in horizontally
reciprocating manner. During such movement, displacement of the
loop portion 55 takes place, with the roller 67 following the loop
portion.
The term "roller" is to be understood very broadly in the present
case. It is to cover roller-like structures, either solid or
hollow, spherical structures and polygonal structures.
* * * * *